1. Field of the Invention
The present invention relates to Liquid Crystal Display (LCD), and more particularly, to a dithering method applied in an LCD and a related dithering module and LCD.
2. Description of the Prior Art
Liquid Crystal Display (LCD) is one of the most important products on the current display market. A signal controller and a driving IC are two extremely important components in the LCD, wherein the signal controller receives R/G/B video signals and data enable signals DE, and generates corresponding control signals accordingly, and the driving IC drives a display panel according to the control signals generated by the signal controller.
In general, a bit number of the R/G/B video signals received by the signal controller is equal to a bit number that the driving IC is capable of processing. Taking the present popular video format for example, the bit number of the R/G/B video signals received by the signal controller is 8-bits, and thus the driving IC utilized in the LCD is capable of processing 8-bit signals. However, the unit price of a driving IC for processing 8-bit signals is more expensive than the unit price of a driving IC for processing 6-bit signals. In order to reduce the cost, some people in academic and industry fields provide dithering techniques for an LCD integrated with a driving IC for processing 6-bit signals that can display frames according to the 8-bit R/G/B video signals. However, all of the conventional dithering techniques have their own disadvantages. For example, some conventional dithering techniques will result in a problem of Gamma degeneracy; that is, each of the R/G/B color fields with original 256 gray levels will degenerate to R/G/B color fields with 253 gray levels. In this way, the input data has 256*256*256=16,777,216 color levels originally, but the LCD is only able to display 253*253*253=16,194,277 color levels, and a total number of about 580 thousands of color levels are missed. This is one of the problems faced by the conventional LCD dithering techniques.